Prior art motor controllers typically measure the speed of the motor and the current flowing through the motor and then regulate it by suitable controlling mechanisms so as to keep the speed constant, or keep the energy input as low as possible, or avoid excessive input current surges, or achieve any other desirable objective. The problem with this approach is that the operating characteristics of motors are such that the current flow is quite erratic, noisy, and chopped up. Hence, the current flow must be averaged over some minimum interval of time, with a filter or the like, in order to establish a reasonably accurate measure of the average current flow at any one time. Experience has shown that sudden load changes on the motor, or other momentary deviations in operation, can cause surges in current flow faster than the minimum interval of time needed for practical measurement. These surges may do damage to the motor or blow fuses. My invention solves these problems.